There’s a well-appointed bathhouse minutes from home so it says something about the odd magic of the more distant Okubo Yu that, when you feel like mixing with people and having a soak, you end up here, at the back of Kappabashi, at this faded place. It’s certainly no-frills. The room, though repainted since this photo from April, has seen better days. Nor is there a sauna or an outdoor rotenburo bath.

But the water is pristine and drawn from a well. It’s heated by one of Tokyo’s few remaining wood-burning bathhouse furnaces. This makes it softer, some people say. Whatever the science, the water here is the hottest of all the sento you have visited, yet for some reason it’s perfectly tolerable. You sit here, boiling, tingling and mesmerized. It’s like your bones are fizzing. Afterward you sleep like a bear. It is becoming a pattern.

There are two jet baths and a red-coloured herb bath of angelica and other ingredients. Smells of camphor and mint, a bit like temple incense. The washing area is austere, and people are quiet. It’s a neighbourhood crowd, unlike the touristy bath in Asakusa.

Okubo Yu has operated since before the war. The current bathmaster is the third generation owner, a stocky man, shy but not unfriendly. He won’t give you an interview, says the woman at the counter. He’s a country fellow. He doesn’t like to talk. In the afternoons you can see him loading the furnace. It looks like a big job. One day you ask him how long the massive pile of wood beside the building will last, and he says, About a month. Most of the fuel appears to be the beams of demolished houses.

Buckets and buckets of rusty nails are lined up in a row, little relics raked from the ashes.

Okubo Yu is at 3-13-10 Matsugaya, Taito-ku tel 03-3844-6369. Closed Fri.